IN 1990, when I was traveling in Japan, my friend Masayuki introduced me to his mother, Mrs. Tadokoro. One night, as the three of us sat together after dinner in her apartment in Osaka, she told me of the firebombing of Tokyo. She was nineteen when the American bombers came, just after midnight on March 10, 1945. Hearing the air-raid sirens, she ran to Kinshi Park. As she ran, she saw an electrical pole glow hot in the flames and then crash down. In the park many people, most with suitcases, waited through the night as sixteen square miles of the city burned. Nothing remained of her house the next morning but some stones. Still, she was lucky. The dead from that one night's bombing numbered 80,000 to 100,000—more than later died in Nagasaki (70,000 to 80,000), and more than half the number who died in Hiroshima (120,000 to 150,000).

August brings the fifty-seventh anniversary of the two famous atomic bombings, justification for which is still a matter of debate. The conventional wisdom that the Hiroshima bomb saved 500,000 or a million American lives is wrong; according to the historian Gar Alperovitz, modern scholarship and also government estimates at the time put likely U.S. casualties from an invasion of Japan, had one been necessary, in the range of 20,000 to 50,000—which is, of course, still a lot. Nor is it the case that Hiroshima was targeted for its military installations; it had some modest military value but was targeted mainly for psychological effect. Yet the bombing clearly did hasten Japan's surrender, and thus saved many American lives (and possibly, on balance, Japanese lives). The much harder question is why the United States rushed—and it did rush—to bomb Nagasaki only three days later. Neither President Harry Truman nor anyone since has provided a compelling answer. In his 1988 history of the nuclear age, McGeorge Bundy, who served as National Security Advisor to Presidents Kennedy and Johnson, wrote, "Hiroshima alone was enough to bring the Russians in; these two events together brought the crucial imperial decision for surrender, just before the second bomb was dropped."

Alongside the two atomic bombings, the firebombing of Tokyo remains obscure. Few Americans have even heard of it, and few Japanese like to dwell on it. When I listened to Mrs. Tadokoro's account, I was struck by her matter-of-fact, detached manner. What happened happened, and war is always bad, and 1945 is ancient history: that was her practical, forward-looking attitude, and I admired her for it. Yet the Tokyo attack deserves the most introspection of all, even as it receives the least.

In the 1930s, as today, Americans set great store by the principle that civilian populations should not be targeted for bombing. "Inhuman barbarism," President Roosevelt called civilian bombing in 1939. Indeed, that was one reason to fight the Japanese: they targeted civilians, we didn't. By 1945, however, the precision bombing of Japan had proved frustrating. "This outfit has been getting a lot of publicity without having really accomplished a hell of a lot in bombing results," Major General Curtis LeMay groused on March 6. So he loaded more than 300 B-29 Superfortress bombers with napalm incendiaries and, on the evening of March 9, ordered them emptied over central Tokyo. LeMay made no attempt to focus on military targets, nor could he have done so with napalm, whose effect that windy night was to burn wooden Japanese dwellings with spectacular efficiency. The victims were "scorched and boiled and baked to death," LeMay later said. Over the next few months the United States dealt with more than sixty smaller Japanese cities in like fashion.

The rationale was that Japan's industrial capability needed to be destroyed and the country's will broken. In fact, however, the Japanese maintained the ability to fight, although they probably lost the capacity to mount any large offensive. In any case, even supposing that the Tokyo firebombing was a success on its own terms, did that justify the targeting of tens of thousands of civilians, with weapons designed to melt them in their homes? If so, what sort of action would not have been justified on grounds of helping to end the war (that is, winning)? In June of 1945, as the historian John W. Dower notes, a military aide to General Douglas MacArthur described the American firebombing campaign as "one of the most ruthless and barbaric killings of non-combatants in all history." It is hard to disagree.

I believe the firebombing of Tokyo should be considered a war crime, a terror bombing, if those terms are to have any meaning at all. It is true that the United States in 1945, in marked and important contrast with, say, al Qaeda in 2001, viewed the targeting of civilians as a last rather than a first resort; and it is true that throughout history even the virtuous have wound up fighting dirty if fighting clean failed; and it is true that sometimes the good must do terrible things to destroy a great evil. But it is also true that if the good find themselves driven to barbarism, they own up afterward and search their souls.

America is better at reforming than at repenting, which is probably just as well. Perhaps America's quiet way of paying its debt to the dead of Tokyo has been to take unprecedented pains, far beyond anything done by any other great power, to design and deploy weapons and tactics that spare civilian lives. A lot of innocent people in Yugoslavia and Afghanistan are alive today as a result. Still, the erasure of the Tokyo firebombing from Americans' collective memory is not a noble thing.

In March, on the fifty-seventh otherwise unmarked anniversary of the attack on Tokyo, a handful of survivors opened a small museum there to memorialize the firebombing. They used private contributions totaling $800,000, which is less than one percent of what Mount Vernon plans to spend on its new museum and visitors' center. Well, it was a start. The next step should be an official museum or memorial—not in Tokyo but in Washington.